Quantifying the evidence for resonant damping of coronal waves with foot-point wave power asymmetry

TL;DR

This study uses Bayesian analysis of CoMP observations to evaluate models of resonant damping and foot-point wave power asymmetries in the solar corona, finding the larger model better explains the data and aids in understanding coronal heating.

Contribution

It introduces a Bayesian framework to compare models of wave damping and asymmetry, highlighting the importance of foot-point effects in coronal wave analysis.

Findings

Larger model with foot-point asymmetry better explains the data

Resonant damping alone is insufficient to account for observed wave power discrepancies

Accurate damping ratio inference requires considering foot-point asymmetries

Abstract

We use Coronal Multi-channel Polarimeter (CoMP) observations of propagating waves in the solar corona and Bayesian analysis to assess the evidence of models with resonant damping and foot-point wave power asymmetries. Two nested models are considered. The reduced model considers resonant damping as the sole cause of the measured discrepancy between outward and inward wave power. The larger model contemplates an extra source of asymmetry with origin at the foot-points. We first compute probability distributions of parameters conditional on the models and the observed data. The obtained constraints are then used to calculate the evidence for each model in view of data. We find that we need to consider the larger model to explain CoMP data and to accurately infer the damping ratio, hence, to better assess the possible contribution of the waves to coronal heating.